820378871 has 4 divisors (see below), whose sum is σ = 883484952. Its totient is φ = 757272792.

The previous prime is 820378859. The next prime is 820378901. The reversal of 820378871 is 178873028.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-820378871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820378841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31553021 + ... + 31553046.

It is an arithmetic number, because the mean of its divisors is an integer number (220871238).

Almost surely, 2^820378871 is an apocalyptic number.

820378871 is a deficient number, since it is larger than the sum of its proper divisors (63106081).

820378871 is a wasteful number, since it uses less digits than its factorization.

820378871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63106080.

The product of its (nonzero) digits is 150528, while the sum is 44.

The square root of 820378871 is about 28642.2567372056. The cubic root of 820378871 is about 936.1342943982.

The spelling of 820378871 in words is "eight hundred twenty million, three hundred seventy-eight thousand, eight hundred seventy-one".